Flying internationally with fly rods and flies isn’t that big a deal. I took two rods with lots of flies to Europe two summers ago.

The biggest hurdle I found is whether or not a country allows rods as carry-on luggage. But I was able to fit a 4-piece rod inside it’s tube diagonally in my suitcase, so I just checked everything.

FYI, the 8’9” ********* was one of the rods I took with me.

I think a versatile 6wt, what I would refer to as a trout 6 at 8’ to 9’. Theb a smaller stream rod, probably 7’6” to 8’ 4wt.

While that rod (or one like it) could well serve almost all purposes on a Montana trip, I always take (at least) two rods on a trip. Putting aside that conditions may not be as expected and you really want a heavier or more delicate rig than anticipated, stuff happens; in the 35 + years I’ve fly fished, I’ve had several rod or reel failures. Having another rig back at the car has saved that day for fishing, even if it’s not a first choice for that spot. Sure, you might be able to get to a shop, buy something, and get back, but even in a heavily visited area, that could be a couple of hours, or maybe all day. But besides the $ cost of that, on a weeklong trip, with unfortunate weather, the time cost could feel a lot higher. It happens that I own multiple rods, and feel there’s really no reason not be prepared for a little trouble; a lot of rod tubes seem to fit two rods, and if not, one’s easy to find. And that the second rod (and reel) is a little more fine-tuned to some of the variety I hope to enjoy is just a bonus.

My Fisher 8'6" (5-8 wt) and Airrite 6'9" (3-5wt). Bases covered.

It wouldn't be a bad idea to have two identical spec rods--in 'glass that would be a 6 weight for all around coverage, the second one as a backup. Similarly, the thinking in my response is that I would have two different fiberglass rods, but relatively close in specification, such that either would do in most circumstances if something happened to the other one. It's the same idea as the old truism, "beware the one-gun man."

Only two rods?.....probably my Dickerson 8014 six weight and my Orvis 7.5 foot Battenkill, both bamboo. For glass, I would want my SA System 7 and my Kennedy Fisher 8 footer for a 6 weight. In graphite it would be my Orvis Far and Fine and my Limestone Special.

Pretty irresistible to take two rods two line weights apart or different lengths but for the same weight. Not mentioned much, a vast range of variety with just a single line weight, in fiberglass let's say a 5 or 6, is possible in different lines and leaders, so luggage could be devoted to that. One DT, one WF+1 of the DT line weight, one intermediate, and a couple of sink tips--one long and moderate sink rate, one short fast sink rate. Five reels, loaded up with a chosen variety of fly lines, one pack of leader/tippet material is the "one gun" way.